Specialist teams are set to undertake precautionary contamination testing on the Wiltshire Air Ambulance station, vehicles and kit as part of the Amesbury poisoning operation.

Charlie Rowley and Dawn Sturgess were both taken to hospital after being exposed to the nerve agent Novichok in the Wiltshire town, with Ms Sturgess passing away days later.

During the testing, the air ambulance base in Semington will close as of 5pm on August 1, with the vehicle being unable to fly during the work.

Wiltshire Police have ensured that paramedics and doctors will remain fully operational using rapid response vehicles.

Parts of Amesbury were cordoned off after two victims were exposed to the nerve agent (Image: Getty Images Europe)

Deputy Chief Constable Paul Mills, who is leading the multi-agency response to the incident said: “We are very aware that this news might cause some concern to our communities.

"The work we are undertaking forms part of the wider ongoing response to the incident and is the next logical precautionary step in the process.

"This highly precautionary activity is focused on ensuring that we take all steps necessary to consider any remediation activity which may be necessary in the longer term to further reduce any residual risk.”

Whilst the risk of contamination remains low, police have stressed that the testing forms part of the wider response to the Amesbury poisoning and is taking place on a precautionary basis.

Wiltshire Air Ambulance will be tested for contamination on August 1

Police and Crime Commissioner Angus Macpherson said; “All agencies are working closely together and are working incredibly hard to ensure the safety of staff and of course of the public.

"Its right that action is taken to rigorously and thoroughly test where the scientific advice dictates its appropriate to do so.

"Public safety must remain the number one priority and I am confident this is at the absolute forefront of any action taken.”

Chief executive of Wiltshire Air Ambulance David Philpott said: “As is normal procedure when our helicopter is unable to fly, our paramedics and doctors will respond to emergencies in Rapid Response Cars, providing critical care to patients.

“We are incredibly proud to provide a lifesaving service in Wiltshire and surrounding counties and thank everyone, including our colleagues at neighbouring air ambulances, who will offer support in the short term.”

Police have set up two dedicated phone numbers for anyone with concerns relating to this incident, staffed by police and public health officers. The Freephone number is 0800 092 0410 or if you cannot dial Freephone, call 0207 158 0124.